Technological advances enable the Michelson interferometer to measure multilayered samples that are tens of millimeters thick, with submicron accuracy.SAM MARGOLIS AND MICHAEL HOUK, BRISTOL INSTRUMENTS INC.White light interferometry (WLI) is a common system of measurement with a long history and a variety of applications, which currently include surface profiling1, medical imaging, and — as in the past — thickness measurement. Also known as coherence scanning interferometry (CSI), vertical scanning interferometry (VSI), and optical coherence tomography (OCT), these systems, regardless of their names, are characterized by the same components: a broadband light source, reflection from one or more surfaces being measured, illumination and light collection optics, and an interferometer...Read full articleRelated content from Photonics MediaARTICLESAlgorithm Delivers Perceptual Reality to Holographic DisplaysResearch at Stanford University may lead to more realistic displays in virtual and augmented reality headsets. 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